Garmin 305 off by 1.5 mi?

So I went out for a nice 40 mi ride, 3rd ride since I got it for Christmas/Birthday. Today I noticed that when I was looking at the route versus the speed/cadence, it did not seem to line up. There was one point where we got to a nice long lonely staight away and I did a nice sprint up to max heart rate ,and then a cool down till the pack caught up.

About 10 miles later we went out 5 mi in a nice paceline, stopped for water, and then returned and stopped again at the park for refills and a potty break.

In all 3 cases the speed "peak" in the case of the sprint or the cadence and speed "valley" in the case of the rest stops, all seem to be off by about 1.5 mi compared to the map. I understand the the GPS is accurate to maybe 100 meters, but 1.5 mi?

I had one of those, and returned it to REI. On my regular commute (which was about 8 miles at the time) it would show me riding anywhere from 3 miles to an astonishing 54 miles once. I downloaded the map data and it showed me zig-zagging like crazy within a 2 mile radius. I returned it the day I was sitting outside, in the open with no line-of-sight obstacles, eating my lunch and gazed to to learn I was traveling at 99.99mph. I also got tired of standing outside on the corner, waiting for sometimes 10 minutes for the piece of crap to pick up the satellites. It didn't always happen, but it happened waaaaay more than it should have, for what I paid. I just got a regular computer after all that.

Say what you will, but I'm now convinced the problem lies with the Garmin mapping software. I have evidence to the contrary. Yesterday I was unable to upload the ride to my favorite mapping site, http://www.ridewithgpd.com but I reported the problem and they diagnosed and fixed the problem yesterday afternoon. Today I uploaded the ride and the speed peak and the two rest stops are spot on as compared to the route map. So the problem has to do with how the Garmin sites are interpreting the GPS data!

I know that RWGPS uses Google maps. Don't know what Garmin uses. Interesting! Garmin is a GPS company and can't get it right!

FURTHER UPDATE. The GPS data files from the 305 are CORRECT. The problem lies in how TC and (until today) Garmin Connect sync the histogram data to the route map. Today's ride was correct in RWGPS (never had the problem) and Garmin Connect is now correct. The problem is still in TC.

FURTHER UPDATE. The GPS data files from the 305 are CORRECT. The problem lies in how TC and (until today) Garmin Connect sync the histogram data to the route map. Today's ride was correct in RWGPS (never had the problem) and Garmin Connect is now correct. The problem is still in TC.

Training Center sucks. Use SportTracks if you are on a PC or Ascent if you are on a Mac.

Connect sucks compared to MotionBased. Connect is only useful for a high level ride summary or sharing the ride with people. If actually want to look at the ride in any detail it's pretty much useless.

Connect sucks compared to MotionBased. Connect is only useful for a high level ride summary or sharing the ride with people. If actually want to look at the ride in any detail it's pretty much useless.

I'm confused. I thought Garmin bought the MotionBased site and has just converted it to Garmin Connect. I never used MotionBased so I don't know how it compares to Connect. I know that Connect is far better than the Garmin Training Center (TC), even the newest version.

Garmin does not have satellites. The GPS system was established and is maintained by the US Military. Everyone uses the same satellites.

Where the hell did you come up with that stupid idea?

Whoever owns and maintains the satellites, doesn't matter. Sorry if my idea is too stupid for you. Doesn't change the fact that the Garmin 305 was beyond unreliable for me. It's your money, waste it however you see fit.

Whoever owns and maintains the satellites, doesn't matter. Sorry if my idea is too stupid for you. Doesn't change the fact that the Garmin 305 was beyond unreliable for me. It's your money, waste it however you see fit.

The satellites are fine, sorry if you are too stupid to use the system effectively.

Nice job, with the personal insult there. You're a real credit to this forum.

Pot. Kettle. Black.

As far as a credit to the forum, think whatever you want, but I get several people asking for advice/input daily. If you are so inclined to search my history you would find that I am in fact very helpful, but I don't tolerate idiots. Of course it's the idiots that think I'm mean. I don't really care.

I'm confused. I thought Garmin bought the MotionBased site and has just converted it to Garmin Connect. I never used MotionBased so I don't know how it compares to Connect. I know that Connect is far better than the Garmin Training Center (TC), even the newest version.

They bought motionbased and phased it out, replacing it with connect. Other than that you can share your ride data in both, they are completely different. Connect is "prettier," but motionbased had far more functionality.

Gentlemen, I'm sure you can express your difference of opinion of the quality of United States Military satellites without calling each other names. I know plenty of people who swear by their Garmin, and plenty of people who have had problems with them. I don't have any personal experience to add, so I'll just say that ya'll should agree to disagree on this point on move on.

Gentlemen, I'm sure you can express your difference of opinion of the quality of United States Military satellites without calling each other names. I know plenty of people who swear by their Garmin, and plenty of people who have had problems with them. I don't have any personal experience to add, so I'll just say that ya'll should agree to disagree on this point on move on.

The satellites are fine. Garmin's receiver implemtnation, especially the 305, is far from perfect.

I got the 305 for Christmas and have logged about 25 rides since. The mileage is very consistent for me. I also use Sport Tracks. The actual mileage is always shorter on Sport Tracks than Garmin Connect, but the variance is less than .004%. LoRok, is it possible that you had a defective receiver? The wealth I get out of the 305 keeps my interest up, pushes me to work harder. But I'm just a technoweenie deep down.

I think its disgusting and terrible how people treat Lance Armstrong, especially after winning 7 Tour de France Titles while on drugs!

As UMD has indicated, the 305, esp the earlier implementations, had some sever design problems. I also think that Garmin's customer service may not have been as customer focused as it appears to be now. Factors like that can lead to a very unpleasant customer experience that engender a "anything but Garmin" attitude.

Too many manufacturers forget that a "product" is more than just the item we take home for the store. For us consumers, it is everything about the experience. LoRok got burned bad. His ire is understandable. His choice of words (Garmin satellites) was either unfortunate or borne out of a misunderstanding of the technology.

The bottom line is even the best of companies make mistakes (look at Toyota!) It's how they recover from that mistake that makes all the difference.